


Heartless

by Darkmoon100 (orphan_account)



Category: Undertale (Video Game)
Genre: Angst will come later, F/F, F/M, First real fanfiction on this site, Frisk and reader are adults, Frisk is a traitor, I'll put warnings, I'm not too good at angst so please forgive me, It's my favorite genre tho, M/M, Maybe - Freeform, No Chara because that's getting old, Or you, Probaby some dark themes, So why not Frisk, The skele is heartbroken, There's language, We need a new villian, You are Flowey, You're a bitch to everyone, huzzah
Language: English
Status: Completed
Published: 2016-06-09
Updated: 2016-07-06
Packaged: 2018-07-13 23:34:11
Rating: Mature
Warnings: No Archive Warnings Apply
Chapters: 5
Words: 4,130
Publisher: archiveofourown.org
Story URL: https://archiveofourown.org/works/7142903
Author URL: https://archiveofourown.org/users/orphan_account/pseuds/Darkmoon100
Summary: <blockquote class="userstuff">
              <p>When the barrier breaks, Asriel turns back from Flowey and stays that way. Even Gaster comes back. But you gave your soul so that Frisk wouldn’t have to, and you wake up with Flowey’s form and personality. All you want is to be left alone, but a certain smiley trashbag won’t let you go.</p><p>Warning: Language, possible dark themes</p>
            </blockquote>





	1. Chapter 1

**Author's Note:**

> I've always wanted a story where Frisk has a companion who falls and journeys with them but when they go to break the barrier Frisk becomes the bad guy (no Chara cause that gets old) and sabotages the other. There were none, so I made one. Also I wanted a Sans x reader where the reader kinda hates Sans but he loves her and he just gets his heart broken over and over again because I'm a sadistic bastard and I want to see him in pain.

I blinked, watching as the monsters cheered and flooded out of the prison they called home. No one seemed to notice that I was gone, and I intended for it to stay that way. I didn’t want to be bothered, so I held my silence and watched all the hugs and kisses that ensued amongst the hooligans. Ugh.

 

It had been a couple of days since I had woken up in Flowey’s form, but I got over it quickly. After all, I knew when I sacrificed my whole soul instead of half mine and half Frisk’s like we agreed that there were going to be consequences. I’d seen weirder, so it didn’t faze me. I had watched as Frisk had woken up days after the barrier shattered, watched everyone hug them and fret over them, even though they had done nothing. Bah! Why should that stupid kid get all the credit for what I’d done? They sabotaged me; instead of giving up half their soul like we promised, they just shoved mine forward and tried to cover themselves from the explosion! Worst of all, it didn’t seem as if they had noticed that I was gone. Maybe they thought I was somewhere in the crowd. I don’t know.

 

I looked at Asriel, holding Frisk’s hand and grinning like the stupid idiot he was. He didn’t deserve this happy ending. It was his fault in the first place. I glanced at Dr. Gaster, his arms around his two sons. His happy smile was disgusting. I’ve never seen the smiley trashbag grin that wide, not even when I agreed to go out on a date with him.

 

I wanted to see the outside, however, so I burrowed my way into the ground and popped out at the cave entrance. This is the farthest I dared go. Really? This is what we had been striving for? A giant ball of light that hurts your eyes? Everyone was pointing to it and exclaiming like I’d seen Alphys do when she watched anime, so I guess it was cool? I would’ve pondered it further, but suddenly a chill ran up my spine. I whipped around and saw Sans glaring at me with cold, empty eye sockets. It was just the main gang now: Frisk, Toriel, Asgore, Undyne, Alphys, Mettaton, Napstablook, Papyrus, Gaster and Sans.

 

“ **w h a t a r e y o u d o i n g h e r e.** ” Ah, I knew that voice so well. At his words, everyone spun around and looked at me. There were varying emotions: surprise, anger, horror. I expected all of them.

 

“I’m just over here living. What are YOU doing here? Don’t you want to go out and look at your twinkly winkly stars?” I spat.

 

“But...Asriel is r-right here.” Alphys stuttered. “There’s no p-possible way that F-Flowey should b-be able to be h-here.” Everyone nodded vehemently at her, then swiveled their heads back to me.

 

“Well, I’m here, so get your air - filled heads over it. I won’t intrude on your little celebration, don’t worry. I’ll just go back to the ruins.” I was about to burrow back down when suddenly, Sans appeared next to me and yanked me out of the ground by my stem. “OWOWOWOWOW LETMEGOYOUSTUPIDFUCKER-”

 

He shook me a bit, then asked me a question I didn’t expect. “Are you the reason we can’t find (Y/N)?” I glanced at him, blinking in surprise, before an evil smirk formed on my face. 

 

“You remembered me? I’m flattered.” His eyes widened and he sucked in a breath, along with everyone else. “I thought you forgot all about me ‘cause Frisk shattered the barrier; they’re the hero now, right? Leave me alone, trashbag. I’m not in the mood.” His bones were rattling by now, I wasn’t sure why but they were. He still wouldn’t let me go. “Don’t you get it, bonehead? My name is-” I didn’t get farther than that. He flung me against the wall and ported a couple feet back to where the rest of them were.

 

I gave a small laugh, before plunging my roots into the ground and winking at him. “What, are you surprised? Why don’t you ask Frisk what they did? I’m not sure how I ended up in this body, but I’m sure it had something to do with the barrier.” They still weren’t speaking. “What, cat got your tongue?”

 

A quiet voice resounded from the right side of the group. “(Y/N)?” It was almost a whisper. I located the source of the sound: Papyrus. Huh. I didn’t now he could be that quiet. I spread my petals and winked again, sticking my tongue out this time too. “Yup, that’s me!”

 

“What happened to you, punk?!” screeched Undyne. I winced at her loud tone, then looked at her, doing my best imitation at a shrug. No one said anything else, so I took that as an invitation to leave. “Well, I’ll just be going now. Have fun with the humans.” I turned to go, before I was pulled out of the dirt again. This time, I got put into a shoe. I whipped around, hissing, to see Frisk’s smiling face, Asriel right behind them.

 

“Don’t worry, (Y/N). We’ll get you back again.”

 

“LET ME GO, YOU TRAITOR!”

 

I don’t know why that pulled my petals so much, but suddenly I was livid. With as much of a roar as I could muster, I sent ‘friendliness pellets’ at Asriel, whipping Frisk with my spiked vines. They both cried out and Frisk dropped the shoe in favor of clutching their eyes. I reached for the soil with my roots, but before I could reach it Frisk screamed out, “NOW, SANS!” I suddenly I was being levitated by a blue magic I knew all too well.

 

He floated me over and they all began to murmur things to me, talking about how they would get me back and how everything would be okay, while I screamed that everything already was okay and to let me go and how I didn’t want to suffer their presence any more than I already had to. They carried me all the way outside to the camp the monsters were setting up and put me in Alphys’ makeshift lab so that I couldn’t burrow down. They gave me sad last looks before leaving one by one. Sans was the last to go, and he whispered, ”I’ll get you back, vertebae. Promise.” He left, clicking off the light and drowning me in shadows.

 

Ha. Vertebae? He thought I still loved him? Not a chance. Not a fucking chance.


	2. Chapter 2

**Notes for the Chapter:**

> Wow, I didn't think that this would have such a positive reception! Thanks to all those who left kudos and comments. I try to only do plot ideas that haven't been done often or at all, so I'm glad this one seems well liked. I actually have no idea where to go with this story though, so I'm open to suggestions. Updates will be entirely random but hopefully relatively close together.
> 
> Also, I had this idea while writing this chapter, and depending on how many want it I will write it as a seperate one shot or story. The prompt would be: What if Trump was the fallen human? (No idea if this has been done before but it seems like a fun idea.)

It had been a week since I’d been taken to the lab. Alphys, Gaster, and Sans had exhausted themselves trying to find a way to ‘fix’ me. I wasn’t broken; if anything, I was stronger than before. But they insisted that there was something wrong with me, and that’s why I was in my current predicament: how to escape one of Alphys’ shots.

“Come on, Flowey, we need to give you your daily injection…” When she was in science mode, she tended to lose her stutter. It was a relief not having to wait an hour before she finished a sentence. Also, I was glad she was so short. They had put me in a glass case so that I couldn’t reach the outside, and if I huddled in the corner she couldn’t reach me, and neither could Sans. Alphys didn’t want Sans to use magic on me in case it did something bad or whatever. And I could just slip through the holes in Gaster’s hands.

I did what I always did when this time of day came around. I hissed at her and recoiled farther back into the glass case. One thing I had noticed, though, was that more often than not they called me ‘Flowey’ and not ‘(Y/N)’. It was fairly relieving to be free of my old identity, I suppose, and I don’t think they had noticed. 

It took all three of them a couple hours to realize they needed someone with longer arms, and who better than Papyrus? I could sense their hesitance at bringing in the cinnamon roll, but if they asked Undyne she would probably suplex me. Asgore and Toriel were busy with politics, Frisk and Asriel hadn’t come to see me once, and Mettaton had already left on tour with Napstablook. I don’t know how he managed to gain the human’s trust so quickly, but he was already one of the most popular performers in the country. How does one achieve that in a week?

I was so caught up in my thoughts that I didn’t realize Papyrus had grabbed me until I felt liquid seep into the soil of my pot. My head shot up to see all four of them smiling rather smugly at me through the closed glass door. That fast, huh? I need to get my head in the game.

Well, at least they were done for the day. Nothing ever happened after injections; all they did was monitor my vital signs. No one spoke to me, no one asked what happened. I knew that no one would believe me if I told them what happened, so I kept it to myself.

_I panted, tired from dodging Asriel’s attacks. Frisk was down, having been hit by Star Blazing one turn ago, but they were getting up. I turned around just in time to see the world go black and Asriel shifted into a different form, even more terrifying than the last. Suddenly, I was frozen. Panicking, I flicked my eyes over to Frisk. Seems they were having the same issue._

_Asriel was saying something, but I couldn’t hear. I was focusing on helping my soul, the only thing left that could move, dodge his attacks. Frisk and I struggled, but we couldn’t move. We tried to reach our file, but nothing happened. We couldn’t save either, but there was something else we could save. We began to talk to our friends. We called out to Toriel and Asgore, calling them Mom and Dad, and they woke up and sobbed. We told Sans and Papyrus a joke; Papyrus let out a scream of frustration and Sans gave a hearty laugh. We told Alphys that anime was real, and she shot up at our words. For Undyne, we punched her in the face, and she let out a mad roar. Then we went back to Asriel and saved him too._

_He bawled into our embrace, and once he had calmed down enough he told us how to break the barrier. We gathered everyone’s hopes and dreams, but it wasn’t enough. We needed the power of one human soul. Frisk and I agreed: one half of each of ours. We could live with half a soul, albeit a bit more difficult. But it was worth it if it meant letting an entire race free. We stepped forward, holding our souls out together. The plan was simple. When we touched our souls to the barrier, it would drain the power at the same time and rate, taking about half of each. Just as we were about to touch the barrier, Frisk pulled their soul back. I turned around, wondering what was wrong, just in time to receive a heart shove in the chest. As I fell backward into the barrier, still clutching my soul, I caught a glimpse of Frisk’s face. They had tears in their eyes, but they were smiling and breathing a sigh of relief. I could feel my face contort into an expression of betrayal._

_The pain was excruciating. All the ones and zeros that made up my point of data ripped apart, dissolving into static...it was more than I could bear, but I wasn’t able to pass out. I screamed out into the empty space, pleading for it to stop, asking for it to end, begging for reprieve. Nobody came of course. No one could help me in this place, though, because they would be torn up as well. I don’t know how long I called, but there was suddenly a figure in front of me._

_Flowey’s body slumped there. It had no face and was void of color, but I was so desperate that I reached out just as I finally faded..._

**Notes for the Chapter:**

> Remember to like and comment. Asriel's encounter was based heavily on the Undertale spoof called Underpants. For those of you who haven't watched it, you should probably go do that.


	3. Chapter 3

**Notes for the Chapter:**

> Well, I figured out the plot, so I'm good on that part now. But if you guys have any writing prompts you want me to do, one shots or stories, comment or message me! (Message here on AO3 cause I don't want y'all to see my Tumblr lol.)
> 
> We've got one chapter to go because I got lazy and didn't want to think of more to write. Maybe two chapters if I think of something else. Enjoy! I have no idea how good this chapter is but I think it's fine.
> 
> WARNING: Some language.

*7 months later cause I needed a time skip*

I guess Alphys injected Sans and Gaster with determination, because they won’t give up even after over half a year. Well, Sans won’t give up - Gaster just wants his son to be happy, so he keeps trying. Alphys gave up a while ago but comes in every now and then if Sans needs help with something. He has this ridiculous notion that I could somehow be changed back, but I didn’t want to go back. I like it just fine in this form, thank you very much.

Sans came and talked to me a lot, after ‘work hours’, when Gaster had already gone to bed. He told me how everyone was doing: Undyne, Papyrus, Alphys, Gaster, and Toriel all worked at the same interracial high school. Frisk and Asriel both attended that high school. What a small world. The only ones who hadn’t stayed were the calculator, the ghost and the overgrown goat. Asgore had gone into politics with the humans and was away on business. The other two were always on some tour or another.

Earlier today, Sans came in and sat down on the table, right next to my glass case. He always tried to get a rise out of me, but I very rarely responded. Tonight though, I was in a talkative mood, so I decided to converse.

“Hey trashbag.” Cue surprised look.

“Hey. How’s it going”

“Fine. Yourself?”

Cue an almost spit take. This was the nicest I was gonna get though. 

“I’m doing good, thank you.” Silence. “Ya know, Frisk was talking about you the other day.” I looked at him in a mix of surprise and boredom. On one hand, I didn’t care what Frisk said, but on the other, I was surprised the backstabber to mention me at all.

“Really now? What did they say?” I couldn’t help it - I was curious.

“Just a passing comment. We were on a date, and they asked how you were doing.”

“Why don’t they just come see me themselves!? Lazy ass kid…” I blinked, then whipped around to face him. “Did you say a DATE?”

He nodded, looking smug. I blinked again, then smirked. “Oh, ha. Ha ha ha. This was just a ploy to get a rise out of me. Very funny, Sans.”

“Actually, it wasn’t a joke. It’s real.” 

I looked at the door, squinting against the moonlight to see who it was. Frisk? I haven't seen them since the barrier broke. Huh, so they got the kid playing along too. But Frisk walked right up to Sans and gave him a kiss on the teeth, which he immediately returned. This went on for about a minute, with me screaming at them to get a room and gagging in the background. It was DISGUSTING.

They finally broke apart and looked at me, smiling smugly. Frisk sat on Sans’ lap and he put his arms around their waist. “So,” Frisk began, an evil look on their face. “What do you think?” She gestured to the hug.

“WHAT I THINK IS THAT NEXT TIME I TELL YOU TO GET A ROOM YOU PICK ONE THAT’S NOT MINE.” I was scarred for life. If that’s what they were going for, then their plan had been successfully accomplished. Frisk looked at me with a look that I couldn’t quite place. Their next question was very blunt.

“Aren’t you jealous?” I began to choke on nothing at that point, and Sans looked up at Frisk with a fairly disappointed look, as though they had gone over not doing this before coming in. After getting over my fight against life for the air around me, I began to laugh. And laugh. And laugh. I don’t think I had ever laughed this hard in my entire life, not even in the human part of it. They both gave me that look now, the one that Frisk had earlier.

“Why would I be jealous? Do you want me to be sad the trashbag found a mate just as trashy as him? Jesus, kid, this is hilarious! Of course I’m not jealous.” I thought for a moment, before I put on my creepy ass smile, complete with blacks holes for eyes, minus the tiny white pupil. My voice changed too. **“S a n s w a s t h e b i g g e s t r e g r e t I e v e r h a d.”**

And expression of hurt formed on his face, as well as fluorescent blue tears. He teleported out of there, leaving Frisk to fall ass first on the table, which was pretty funny. But hey, who knew the skeleton was so sensitive? I didn’t.

Frisk glared at me. “Why would you DO SOMETHING LIKE THAT? AFTER ALL THE HELP HE”S GIVEN YOU!” I gave her the “bitch, where” expression and let her continue. “EVEN AFTER HE FOUND A WAY TO CURE YOU-”

“Wait, what?” I was confused. Sans had never mentioned anything about a cure. I felt panic seep through my veins. I didn’t want to go back! Emotions, no powers, human life in general...what was left for me there. Well, to be fair, there wasn’t much left for me stuck in a glass case either. But I prefer that to being a _human._

“Didn’t he tell you? The surgery is tomorrow.” With that, Frisk walked out the door.

What the actual fuck?


	4. Chapter 4: The end.

**Notes for the Chapter:**

> Wow. Two chapters in two consecutive days. New record for me. The amount of HTML configuration in this chapter is unreal.
> 
> This is the end. I think it's kinda bad, but you let me know what you think. Remember, if you have a story request/prompt, message me! It doesn't matter if it's unorthodox or regular, fluff or smut, canon or your own ship, OCs or generic characters, reader insert or third person, I will try and write it. I only can write a limited number of fandoms though. That include FNaF, almost all the Undertale AU's, some Assassin's creed, a number of animes, vocaloid, and a couple of other things. Just let me know.
> 
> Like I said, it's kinda bad. Any questions, just comment. I've been told (by absolutely no one because I don't let anyone read my shit) that the last bit is a bit confusing. 
> 
> EDIT: I just remembered that there's no messaging on AO3. So, drop a message at my Tumblr or as a comment on one of many stories.  
> Tumblr:randomgirl4364 (look for the picture of Rebornica's Mike)

This must be the end, huh?

I was strapped down to a table, roots constricted by zip ties. Fucking zip ties. How pathetic is that? Everyone was gathered around my table. Alphys, Sans and Gaster were murmuring amongst themselves, making last minute adjustments and hopefully making sure everything would work.

“Alright, (Y/N).” Alphys turned around and addressed me. I snarled at her mention of my past name. “We’re going to try this now.” She held up a pulsating soul with all the colors of the original 7: red for determination, orange for bravery, yellow for justice, green for kindness, teal for patience, blue for integrity, and purple for perseverance. Undyne held her hands over the middle of my stem in a CPR position and drew them outward slowly. An faint outline of a cartoonish heart floated out of nowhere and hovered in front of me. Alphys began to push the soul towards the silhouette of the heart floating above me.

“NONONONONONONONONONONONONO-” I couldn’t stop screaming. This was being done to me without my consent. They were all giving me that look of ‘you’ll thank me for this later’ but I wasn’t gonna thank them for it. I wanted to live as a goddamn flower and if they didn’t let me do that then fuck them.

Finally, Alphys shoved it all the way in. I stopped screaming and struggling. I couldn’t move at all. My vision began to go dark, and the last thing I heard was panicked yelling before everything went black.

\---------------------------------------------------------------------------------------------------------------------

I was watching my entire life flash before my eyes, and I couldn’t stop it.

_I drew a mustache on my dad’s sleeping face, my mother giggling as I worked with the Sharpie._

I don’t want this.

_I ran through the mall with my parents on my heels, trying desperately to keep me under control and laughing all the while. All I wanted to do was get to the toy shop there before it closed._

Make it stop.

_We marveled at the size of the hole on top of Ebott. I was well behind the safety line. Suddenly, I was picked up. I turned aroound to see the face of a masked man. There was screaming as I flew through the air towards the pit, another child meeting my same fate._

I said MAKE IT STOP!

Suddenly, the memories rewinded and stopped at a particular one. I began to cry when I saw which one it was.

_“Mommy?” I asked as she tucked me in. She hummed in response. “Can you sing the lullaby?” She smiled and took a deep breath._

**_“Sono yume wa kokoro no ibasho,_** _Your dreams are where your heart is,_

 ** _Inochi yori koware yasuki mono._** _They're more fragile than life itself._

 ** _Nando demo sutete wa mitsuke,_** _Over and over you cast them aside_

 ** _Yasuraka ni._** _Only to find more._

 ** _Saa, nemure._** _Now, rest in peace._

 

 ** _Myakuutsu shoudou ni_** _Pounding impulses defile_

 ** _Negai wa okasare._** _The things we wish for._

 ** _Wasurete shimau hodo_** _And the more we forget_

 ** _Mata omoidasu yo._** _The more we remember again_

 

 ** _Kono utsukushiki zankoku na sekai de wa,_** _In this beautiful cruel world,_

 ** _Mada ikiteiru koto “naze” to tou bakari de._** _All I can do is ask why we are still alive._

 ** _Aa, bokutachi wa kono tsuyosa yowasa de,_** _Oh, with our strength and our weakness,_

 ** _Nani wo mamoru no darou_** _What are we going to protect_

 ** _Mou risei nado_** _If there's no sense_

 ** _Nai naraba?”_** _To anything anymore?_

 

I wanted my life back. My emotions. My memories. My feelings. My relationships. My mishaps. My pleasures. Everything. I want it all back. Just before my pixels dissolve into 0s and 1s once more, I whisper, ”Please.”

 

Nobody heard.


	5. Epilogue

**Notes for the Chapter:**

> For A in the comments section. MORE HTML FORMATTING.

**_5 years later_ **

~ Sans’ POV ~

I knelt by the small grave, surrounded by planted yellow flowers, we had erected for (Y/N), on the verge of tears. I had only been trying to help. I hadn’t meant for that to happen.

Frisk, my mate of 3 years, had decided not to join me. They still sniffed and walked away whenever we mentioned Flowey, whether it be (Y/N) or Asriel. I still don’t know why they hate her so much, and they have yet to tell me. I sat down and traced the letters on the stone. Tears welled in my eyes and forged paths down my cheekbones. I just wanted her back, even if it would be for five minutes.

As cliché as it sounds, I never got to say goodbye.

A song came into my head; a song she used to sing in the underground. When I asked about it, she told me she had made it up after her brother had died. She seemed so guilty about it, and I didn’t understand. The lyrics weren’t in english, so she had translated. But the way the lyrics told the story, it made it seem like her fault. I’m sure it wasn’t like that. 

Regardless, I began to sing the English version, since that was all I knew:

_In a town by a port looking out onto the sea,_   
_Alone on the sand stands a girl crying._   
_And a custom persists and today it still exists,_   
_Traditions from long long ago._

_“Write down a wish on a piece of parchment,_   
_Then place it in a bottle._   
_If you let it flow then someday it will grow,_   
_And your heart’s desire will be real.”_

_Flow along, glass bottle, and please don’t take too long,_   
_Cause what I want the most is in that message._   
_And on the other side of this sunset,_   
_Right there, my wish will disappear._

_You would always do everything I asked you to,_  
 _Really any request of mine, and I still_   
_Was a spoiled selfish brat and I really regret that._  
 _I always caused problems for you._

_The you who granted me every single wish_   
_Are no longer here by me._   
_On this blue sea, will all my feelings_   
_Arrive to where you are?_

_Flow along, little wish, and please don’t take to long,_   
_To take away my tears and all my regret._   
_It was too late by then to fix my sins,_   
_When they’d taken you far from me._

I pause for a moment, where I remembered there to be an instrumental. I was almost done with the song, but I was choking on tears and drowning in guilt. Still, I forged on.

_Flow along, glass bottle, and please don’t take too long,_   
_Cause what I want most is in that message._   
_And on the other side of this sunset,_   
_Right there, my wish will disappear._

_Flow along, little wish, and please don’t take too long,_   
_To take away my tears and all my regret,_   
_“If we’re ever reborn, I hope in my next life…”_

**_I hope we meet again._ **

As I stood up and walked away, I could have sworn that one of the flowers was smiling at me.

**Notes for the Chapter:**

> Song is Regret Message by mothy. Lyrics were taken from moine5142's book on Wattpad, which in turn were taken from MissingNO on YouTube.


End file.
